IMHO (i've said this before)
Our current G14 SEEMS to preform best BLOW 16K. Many paid a price for that in the DGS scenario (IMHO)
Flyin that thing at 30K + was .... ugh, wallowed and had difficulty maintaining alt much less fighting!
Our K4 SEEMS to preform best ABOVE 6k. Compared to the G14 was a joy to fly at 30k+ and you could fight with it up there!
We lack a plane!
IMHO the G10 with a slightly altered FM from the K4 ( about 25mph slower at altitude maybe) would be perfect for scenarios and such. It would fit right in!
Plus the G10 was a HIGH alt fighter!
The G14, from what I've read, was a GROUND attack plane. In some cases it was reported to carry 2 gondolas under each wing and in rare cases even another 2 gondolas in some cases for a total of 5 20mm cannons, and a 500k bomb. This was during it's ground attack role!
Yes in a pinch the G14 was used against high alt bombers.
As to the field modifications thing....
the F4 was equipped with gonds (many were used to attack allied bombers during the early years of the allied bombing efforts) and used to have that option in AH but at some point that option was removed. Perhaps this was due to complaints of it's effectiveness? (loved the F4 with gonds!)
lets see, 109 ALL used to have excellent down elevator performance (which BTW was/is SUPPOSED? to be the case) And could do a snap roll that was difficult for other planes to follow. But when AHII came out that was GONE. 
109g6 used to have the 30mm options but was removed. Not sure why this happened. 
109g10 was a great plane! Had options for a 20mm or 30mm hub and you could add 20mm gonds. Flew poorly with the gonds mind you but oh could it hit! (BTW referred HTC to an article about a current comparison of a G10 (ORIGINAL) to a pony, and 2 aviations greats both claimed the G10 OUT TURNED the pony! The pony could out run the G10 of course.) 
Would love a slightly slower G10 with the 20mm or 30mm hub option and a gonds option. 
IMHO would make the CT and scenarios much more enjoyable if these things were put back in BUT....................
Guess all the noob pony, spit, n lala7 drivers cried to much?????
What? they want a free ride or something?
The Allies won the war so their planes must have been UBER?
Superiority thing? Allied rides were just better? Only by a small margin. AND that margin isn't enough, and IMHO shouldn't be enough, to protect a noob pilot in AHII.
GEEZ it's like these people automatically think the allies had it EASY in the airwar during WWII?
IF SO, NOT TRUE! MANY Allied pilots did not RTB due to LW planes and pilots!
The fightin was HARD! and furious and dangerous for ALL involved.
Several writers have made reference to the NUMBERS put forward by the Allied effort being a telling factor in the war. Get that? NUMBERS! Yes the NUMBER of planes flying and fighting on the Allied side was a BIG contributing factor!
Sorta like the Sherman against the Tiger. The Allies figured they would lose 3 or 4 Shermans for every Tiger taken out. They didn't try to field a superior tank (at 1st anyway) they fielded MORE tanks. And overwhelmed with NUMBERS.
Now I see someone wants the pony to turn better? IMHO it turns about where it should?